Phospholipase polypeptide and a DNA encoding same

Abstract

The invention relates to a DNA sequence that encodes a polypeptide with phospholipase activity and was isolated from Aspergillus and sequences derived therefrom, polypeptides with phospholipase activity encoded by these sequences as well as the use of these polypeptides for degumming of vegetable oil, for the preparation of dough and/or bakery products, for the preparation of dairy products, for processing steps in the textile industry and for related applications.

The invention claimed is: 
     
       1. An isolated polypeptide with phospholipase activity selected from
 a) a polypeptide that is encoded by the coding region of a DNA selected from the group consisting of 
 i) a DNA that comprises the nucleic sequence of SEQ ID NO: 1, 
 ii) a DNA that encodes a protein, wherein said protein has the amino acid sequence of SEQ ID NO: 2, and 
 iii) a full complement of the DNA of (i) and (ii), 
 b) a polypeptide sequence comprising the amino acid sequence of SEQ ID NO: 2 or obtained therefrom, having at least 92% identity to SEQ ID NO:2, 
 c) a polypeptide with a sequence that has at least 92% identity to amino acids 33 to 633 of SEQ ID NO: 2, and 
 d) a polypeptide that is encoded by a nucleic acid sequence that hybridizes under stringent conditions which comprise hybridization at 65° C., 18 h in dextran sulphate solution, washing of the filter for 30 min each, first with 6×SSC, twice 2×SSC, twice 2×SSC, 0.1% SDS and 0.2×SSC at 65° C., with 
 (i) nucleotides 530 to 2388 of SEQ ID NO: 1, 
 (ii) a cDNA sequence comprising nucleotides 530 to 2388 of SEQ ID NO: 1, 
 (iii) a full complementary strand of (i) or (ii). 
 
     
     
       2. An isolated polypeptide with phospholipase activity wherein the polypeptide
 has a molecular weight in the range of 63 to 76 kDa and may also be present unglycosylated as fragments of 18.4 kDa and 46.6 kDa, 
 hydrolyzes at least one of the two fatty acids of lecithin, 
 shows no lipase activity, 
 has an increased thermostability, and 
 is isolated from an organism of the genus Aspergillus, wherein the polypeptide comprises the sequence of SEQ ID NO:2. 
 
     
     
       3. The isolated polypeptide of  claim 2  wherein the polypeptide is isolated from  Aspergillus fumigatus.    
     
     
       4. The isolated polypeptide of  claim 3  wherein the polypeptide is immunologically reactive with an antibody directed against the sequence of SEQ ID NO: 2. 
     
     
       5. A phospholipase composition comprising the isolated polypeptide of  claim 1  combined with additives. 
     
     
       6. The phospholipase composition of  claim 5  further comprising one or more additional enzyme(s) for food or animal feed.